Decreasing the urban carbon footprint with woody biomass biochar in the United States of America

Abstract

Urban centers are places with a high human population concentration, and they can pose social, economic, and environmental challenges. These challenges are accentuated by the increased use of available open space for housing and industrial expansion, leading to elevated energy consumption, increased pollution, higher carbon emissions, and, consequently, adverse effects on human health. Many of these issues also contribute to the acceleration of climate change. There are several ways to decrease these problems through the expansion of greenspaces that conserve biodiversity, decrease air pollution, improve human well-being, and reduce human health risks, while also allowing people to enjoy the benefits of ecosystem services. This review is aimed at professionals who can manage urban landscapes - including adjacent forests, urban parks, tree beds, or home gardens that produce biomass that, together with other non-chemically treated wood waste, could be used to produce and use biochar. Biochar-amended soils provide the benefits of increased carbon sequestration, water retention, and soil productivity and can also decrease stormwater runoff. In addition, a small number of cities around the world have adopted biochar as a nature-based solution to decrease the impacts of climate change. We point out the opportunities and benefits of converting urban wood waste into biochar, how cities can improve their green environments, and, at the same time, produce energy from waste that would otherwise end in landfills with no use or value. Finally, based on previous assessments of wood waste in the United States of America, we estimate the biochar potential to sequester CO₂.

Keywords

Biochar / carbon sequestration / urban forests / cities / wood waste / climate change

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